(1) Field of the Invention
The present invention relates to an image processor and an image display apparatus; and, more particularly, to an image processor that includes a configuration for converting frame rate of an input image signal and an image display apparatus.
(2) Description of the Related Art
A technique called frame rate conversion has been recently introduced for offering better moving image performance. It uses frames included in an image signal and a motion vector of the input image signal and combines interpolation frames created in an apparatus to generate a signal of a new frame sequence. Accordingly, it becomes possible to offer better moving image performance by improving unnatural motion such as a feeling of afterimage or unstable image in a display of moving images.
In order to improve moving image performance more, it is necessary to generate an interpolation frame with high accuracy. This in turn requires raising the detection accuracy for a motion vector used to generate an interpolation frame. A prior art technique related to the improvement of the detection accuracy for a motion vector is disclosed in Japanese Patent Application Publication No. 2006-165602, for example. The technique involves inserting an interpolation frame between two temporally successive frames included in an input image signal. In detail, plural frame pixel pairs at point symmetric positions about an interpolated pixel that constitutes the interpolation frame are extracted from a predetermined area, and a pixel direction having a minimum difference between the pixels is designated as a motion vector.